Napa County Baseline Data Report, Chapter 16, Groundwater Hydrology

Napa County | November 30th, 2005

This chapter summarizes the basic groundwater hydrology of Napa County and documents the construction of a local integrated groundwater model. The groundwater hydrology a

This chapter summarizes the basic groundwater hydrology of Napa County and documents the construction of a local integrated groundwater model. The groundwater hydrology analysis and model development were designed to establish a baseline of existing conditions to support countywide programs.

Napa County Comprehensive Groundwater Monitoring Program 2016 Annual Report and GASGEM Update

Napa County | March 15th, 2017

A Napa County Groundwater Monitoring Plan 2013 (Plan) was prepared to formalize and augment groundwater monitoring efforts conducted as part of a Comprehensive Groundwate

A Napa County Groundwater Monitoring Plan 2013 (Plan) was prepared to formalize and augment groundwater monitoring efforts conducted as part of a Comprehensive Groundwater Monitoring Program. The Plan recommended annual reports on groundwater conditions and modifications to the countywide groundwater monitoring program as needed. This 2016 Annual Report is the third such report submitted to the Napa County Board of Supervisors.

Napa Valley Subbasin Groundwater Sustainability Plan

Napa County | January 31st, 2022

National assessment of river protection in the United States

Nature Portfolio (Springer Nature) | January 9th, 2026

To address the enduring and deepening crisis facing fresh waters, many nations have recently set bold targets for freshwater protection. However, the lack of comprehensiv

To address the enduring and deepening crisis facing fresh waters, many nations have recently set bold targets for freshwater protection. However, the lack of comprehensive databases and integrative frameworks hampers a robust evaluation of current freshwater protections and prioritization of future opportunities to meet these goals. This study provides a comprehensive assessment of river protection for the USA by reconciling the disparate array of major federal, state, tribal and private protection mechanisms into a single, multifaceted index. We report that just over one tenth of the river length of the contiguous USA and less than one fifth of rivers nationwide are currently protected at a level deemed viable. Lowland headwater streams and intermittent watercourses are consistently underprotected. Protection is also often spatially misaligned with other conservation objectives, where only a small fraction of watersheds with high biodiversity, habitat intactness and importance to drinking water supply are adequately (30% of river length) protected. Our assessment of river protection highlights the urgency to increase new and fortify existing protections for rivers in the years to come if we are to meet ambitious conservation targets, reverse the curve of biodiversity loss and ensure that healthy rivers benefit everyone.

National Audubon Society v. Superior Court of Alpine County

Supreme Court of California | February 17th, 1983

National hydrologic connectivity classification links wetlands with stream water quality

Nature Portfolio (Springer Nature) | April 6th, 2023

Wetland hydrologic connections to downstream waters influence stream water quality. However, no systematic approach for characterizing this connectivity exists. Here usin

Wetland hydrologic connections to downstream waters influence stream water quality. However, no systematic approach for characterizing this connectivity exists. Here using physical principles, we categorized conterminous US freshwater wetlands into four hydrologic connectivity classes based on stream contact and flowpath depth to the nearest stream: riparian, non-riparian shallow, non-riparian mid-depth and non-riparian deep. These classes were heterogeneously distributed over the conterminous United States; for example, riparian dominated the south-eastern and Gulf coasts, while non-riparian deep dominated the Upper Midwest and High Plains. Analysis of a national stream dataset indicated acidification and organic matter brownification increased with connectivity. Eutrophication and sedimentation decreased with wetland area but did not respond to connectivity. This classification advances our mechanistic understanding of wetland influences on water quality nationally and could be applied globally.

National Marine Fisheries Service Biological Opinion for the Long-Term Operations of the Central Valley Project and State Water Project

National Marine Fisheries Service (NMFS) | June 3rd, 2009

The purpose of this document is to present NOAA’s National Marine Fisheries Service’s (NMFS) biological and conference opinion (Opinion), about whether the U.S. Burea

The purpose of this document is to present NOAA’s National Marine Fisheries Service’s (NMFS) biological and conference opinion (Opinion), about whether the U.S. Bureau of Reclamation’s (Reclamation) proposed long-term operations of the Central Valley Project (CVP), operated in coordination with the State Water Project (SWP; hereafter referred to as CVP/SWP operations, the proposed action, or the project), is likely to jeopardize the continued existence of the following species: Endangered Sacramento River winter-run Chinook salmon (Oncorhynchus tshawytscha, hereafter referred to as winter-run) Threatened Central Valley spring-run Chinook salmon (O. tshawytscha, hereafter referred to as spring-run) Threatened Central Valley (CV) steelhead (O. mykiss) Threatened Central California Coast (CCC) steelhead (O. mykiss) Threatened Southern Distinct Population Segment (DPS) of North American green sturgeon (Acipenser medirostris, hereafter referred to as Southern DPS of green sturgeon) Endangered Southern Resident killer whales (Orcinus orca, hereafter referred to as Southern Residents) or destroy or adversely modify the designated critical habitat of the above salmon and steelhead species, or proposed critical habitat for Southern DPS of green sturgeon. This Opinion is based on the best scientific and commercial information available.

National Strategy for the Development of Regional Nutrient Criteria

U.S. Environmental Protection Agency (EPA) | June 1st, 1998

In February of this year, President Clinton and Vice President Gore released a comprehensive Clean Water Action Plan. The Action Plan provides a blueprint for Fed

In February of this year, President Clinton and Vice President Gore released a comprehensive Clean Water Action Plan. The Action Plan provides a blueprint for Federal agencies to work with States and others stakeholders in restoring and protecting the Nation’s water resources and addresses three major goals: enhanced protection from public health threats posed by water pollution; more effective control of polluted runoff; and promotion of water quality restoration and protection on a watershed basis. A key part of the Action Plan provides for expanded efforts to reduce nutrient overenrichment of waters. Nutrients, in appropriate amounts, are essential to the health of aquatic systems. Excessive nutrients, however, can result in excessive growth of macrophytes or phytoplankton and potentially harmful algal blooms leading to oxygen declines, imbalance of aquatic species, public health threats, and a general decline in the aquatic resource. Recent reports on water quality conditions provided by States indicate that nutrients are the leading cause of impairment in lakes and coastal waters and the second leading cause of impairment to rivers and streams. Nutrient overenrichment has also been strongly linked to the large hypoxic zone in the Gulf of Mexico and to recent outbreaks of the toxic microorganism Pfiesteria along the Gulf and Mid-Atlantic coasts. The Action Plan calls on EPA to accelerate the development of scientific information concerning the levels of nutrients that cause water quality problems and to organize this information by different types of waterbodies (e.g. streams, lakes, coastal waters, wetlands) and by geographic regions of the country. EPA is also to work with States and Tribes to adopt criteria (i.e. numeric concentration levels) for nutrients, including nitrogen and phosphorus, as part of enforceable State water quality standards under the Clean Water Act.

National trends in drinking water quality violations

National Academy of Sciences (NAS) | February 27th, 2018

Ensuring safe water supply for communities across the United States is a growing challenge in the face of aging infrastructure, impaired source water, and straine

Ensuring safe water supply for communities across the United States is a growing challenge in the face of aging infrastructure, impaired source water, and strained community finances. In the aftermath of the Flint lead crisis, there is an urgent need to assess the current state of US drinking water. However, no nationwide assessment has yet been conducted on trends in drinking water quality violations across several decades. Efforts to reduce viola- tions are of national concern given that, in 2015, nearly 21 million people relied on community water systems that violated health- based quality standards. In this paper, we evaluate spatial and temporal patterns in health-related violations of the Safe Drinking Water Act using a panel dataset of 17,900 community water systems over the period 1982–2015. We also identify vulnerability factors of communities and water systems through probit regres- sion. Increasing time trends and violation hot spots are detected in several states, particularly in the Southwest region. Repeat viola- tions are prevalent in locations of violation hot spots, indicating that water systems in these regions struggle with recurring issues. In terms of vulnerability factors, we find that violation incidence in rural areas is substantially higher than in urbanized areas. Meanwhile, private ownership and purchased water source are associated with compliance. These findings indicate the types of underperforming systems that might benefit from assistance in achieving consistent compliance. We discuss why certain violations might be clustered in some regions and strategies for improving national drinking water quality.

National-Scale Flood Hazard Data Unfit for Urban Risk Management

American Geophysical Union (AGU) | July 19th, 2024